Use the Office 365 Setup wizard to perform an IMAP migration

The advance setup wizard can run automated checks to discover how your current environment is set up and then, based on what is found, recommend a path to Office 365. If you tell Office 365 Setup wizard that your source email system uses IMAP, and you have fewer than 151 mailboxes, it recommends that you use the Office 365 Setup wizard to copy your users email to Office 365 by using IMAP migration.

The first step is to tell Office 365 that you own the domain or domains you'll be bringing to office 365.

Note: You'll need to repeat these steps for each domain that you own and want to use in Office 365.

On the Let's personalize your setup page, choose Yes, I need to copy data for my users and then:

In the What is your current email system? box, choose IMAP (outlook.com, Hotmail, Gmail).

In the How many users do you have? box, specify the number of users (less than 151).

Note: In order to use the Office 365 Setup wizard to migrate emails to Office 365, the number of users has to be less than 151. You can, however, run the Office 365 Setup wizard multiple times if you want to migrate more than 150 IMAP accounts.

On the What you need to know about domains and DNS page, choose Let's get started.

If you want to learn more about domains, view the video on the page.

On the Which domain do you want to use? page, type in your domain, for example, contoso.com.

In this step, the admin account will be updated to the domain you added and then you can use Office 365 Setup wizard to add users.

On the Let's update your current Office 365 to <your domain name> page, note the new administrator account's user name, select it, and then choose Update selected users to update the administrator account to use the new domain.

On the Sign out to complete the change dialog box, select Sign out to continue. You will have to sign in by using your new user name. Office 365 Setup wizard will bring you back to the setup step you were on after you sign in.

Note: If you run the Office 365 Setup wizard multiple times, you will have to add the admin account only the first time you run it.

After you sign in, you will see the Skipping add users page. Select Next.

Read the information on the Get ready to copy data to Office 365 page and click Next.

On the Add new users page, enter a first name, last name and email alias to the table and then choose + Add a row (1) to enter more users.

You can also choose Use a CSV file to bulk add users (2) to add many users at once.

When you are done, click Add these users.

On the <number of users> was added successfully page, click Next and follow the instructions to install the Microsoft Office apps. You might not see this page if your subscription does not include the desktop apps.

You can also skip this page and install the apps later.

On the Copy data page, select each user that you want to migrate the email for, and in the Source email address box enter the IMAP enabled account that you are copying the email from. This can be the same as the Office 365 address if the user name and domain are the same, but it can also be a Gmail address, outlook.com address, etc.

Enter the Password for the source email for each user, and then click Next to start copying emails.

On the Add your server connection page, enter the IMAP server name, the Port number and the Security type and then choose Copy data.

On the Copy data in progress page you can monitor the status of the migration. Once the migration is done, click Next to continue setting up your domain, as described in Add users and domain to Office 365.

Note: If you plan to run the Office 365 Setup wizard more than once, click the X on the upper-right corner to exit the wizard, and when prompted, choose No, I want to start over. This will allow you to rerun the wizard if you want to copy email in smaller batches. When you are done with the last batch, you can finish setting up your domain.